My son is 4 years old but he is a very big kid. I bought them small and they were too cozy. He woke up sick from the elastic around his waist. He wears a size 6/7 shirt and is about the height of a 7 year old so a medium size fits him perfectly.
Comfortable & Practical City Threads Underwear: Sensitive-Friendly Boys' Clothing
47 Review
π¦ ViCherub Boys' Black Large Underwear - Pack of 3 | Boys' Clothing Collection
42 Review
π¦ HLMBB Dinosaur Toddler Underwear Training | Boys' Clothing for Easy Potty Training
44 Review
π Brix Boys Long Sleeve Tees - Optimized Clothing for Boys
42 Review
Boys' Adidas Active Sports Tricot Athletic Clothing
45 Review
π Bold Pack Sleeve Active Hoodie Sweatshirt Set for Boys' Clothing - Stylish and Comfortable!
47 Review
π Fruit of the Loom 6 Pair Cushion Ankle Boys' Clothing: Comfy and Stylish Selection for Active Boys
57 Review
π₯ Stay Warm and Active with Rocky Fleece Thermal Underwear Bottoms for Boys
44 Review